OSI & TCP-IP MODEL EXAM
QUESTIONS & VERIFIED CORRECT
ANSWERS 100%
Layers Of The OSI model - Correct Answer ✔✔ Layer 1 - Physical
Layer 2 - Data link
Layer 3 - Network
Layer 4 - Transport
Layer 5 - Session
Layer 6 - Presentation
Layer 7 - Application
What does OSI abbreviation stand for? - Correct Answer ✔✔ Open Systems
Interconnect
What happens at the Physical Layer - Correct Answer ✔✔ At this layer, binary
expressions (that is, a series of 1s and 0s) represent data. A binary expression is made
up of bits, where a bit is a single 1 or a single 0.
How bits are represented on the medium
Wiring standards for connectors and jacks
Physical topology
Synchronizing bits
Bandwidth usage
Multiplexing strategy
Example of real world Physical Layer - Correct Answer ✔✔ * Ethernet, DSL, ISDN,
modems
* 568A/B standards
* Bus, Ring, Star, Mesh
* 10BASE-T, 10BASE2, etc.
* 802.11x standards
* T1 and other T-carrier links
* SONET/SDH
* Optical Transport Network (OTN)
What happens at the Data Link Layer ? - Correct Answer ✔✔ This layer is concerned
with packaging data into
frames and transmitting those frames on the network, performing error
detection/correction, uniquely identifying network devices with an address, and handling
flow
control.
, Three Characteristics of the MAC sub-layer @ level 2. - Correct Answer ✔✔ Assigns a
48-bit address assigned to a device's network interface card (NIC).
Devices at this layer view a network as a logical topology, like a bus or a ring.
Implement some strategy for determining when a device is allowed to transmit on the
media, to minimize signal interference/collision.
Characteristics of the Logical Link Control (LLC) sub-layer @ layer 2. - Correct Answer
✔✔ Provides an acknowledgement to the other device to confirm the message was sent
Prevents the user from being overwhelmed with data by limiting the volume of data that
can be sent at any one time.
Informs the sender if any sent data was corrupted or not sent completely.
Coordinates the transmission of data, so both sides know what to expect and when.
Layer 3: The Network Layer - Correct Answer ✔✔ This layer is responsible for routing,
which does not specify how the data is passed, but rather provides the mechanisms to
do so.
Responsible for route selection.
At this layer, the logical grouping of data is referred to as a packet.
Transport Layer (Layer 4) - Correct Answer ✔✔ This layer acts as a dividing line
between the upper
layers and lower layers of the model. Data is encapsulated or decapsulated, and sent
on the appropriate path.
Provide mechanisms to transport data between network devices.
Incorporates error checking, service addressing, and segmentation.
Service addressing at the Transport Layer - Correct Answer ✔✔ Protocols such as
TCP/IP support many network
services. The transport layer ensures that data is passed to the right service at the
upper layers of the OSI model.
Segmentation at the Transport Layer - Correct Answer ✔✔ To traverse the network,
blocks of data need to be broken
into packets of a manageable size for the lower layers to handle. This process, called
segmentation, is the responsibility of the transport layer.
QUESTIONS & VERIFIED CORRECT
ANSWERS 100%
Layers Of The OSI model - Correct Answer ✔✔ Layer 1 - Physical
Layer 2 - Data link
Layer 3 - Network
Layer 4 - Transport
Layer 5 - Session
Layer 6 - Presentation
Layer 7 - Application
What does OSI abbreviation stand for? - Correct Answer ✔✔ Open Systems
Interconnect
What happens at the Physical Layer - Correct Answer ✔✔ At this layer, binary
expressions (that is, a series of 1s and 0s) represent data. A binary expression is made
up of bits, where a bit is a single 1 or a single 0.
How bits are represented on the medium
Wiring standards for connectors and jacks
Physical topology
Synchronizing bits
Bandwidth usage
Multiplexing strategy
Example of real world Physical Layer - Correct Answer ✔✔ * Ethernet, DSL, ISDN,
modems
* 568A/B standards
* Bus, Ring, Star, Mesh
* 10BASE-T, 10BASE2, etc.
* 802.11x standards
* T1 and other T-carrier links
* SONET/SDH
* Optical Transport Network (OTN)
What happens at the Data Link Layer ? - Correct Answer ✔✔ This layer is concerned
with packaging data into
frames and transmitting those frames on the network, performing error
detection/correction, uniquely identifying network devices with an address, and handling
flow
control.
, Three Characteristics of the MAC sub-layer @ level 2. - Correct Answer ✔✔ Assigns a
48-bit address assigned to a device's network interface card (NIC).
Devices at this layer view a network as a logical topology, like a bus or a ring.
Implement some strategy for determining when a device is allowed to transmit on the
media, to minimize signal interference/collision.
Characteristics of the Logical Link Control (LLC) sub-layer @ layer 2. - Correct Answer
✔✔ Provides an acknowledgement to the other device to confirm the message was sent
Prevents the user from being overwhelmed with data by limiting the volume of data that
can be sent at any one time.
Informs the sender if any sent data was corrupted or not sent completely.
Coordinates the transmission of data, so both sides know what to expect and when.
Layer 3: The Network Layer - Correct Answer ✔✔ This layer is responsible for routing,
which does not specify how the data is passed, but rather provides the mechanisms to
do so.
Responsible for route selection.
At this layer, the logical grouping of data is referred to as a packet.
Transport Layer (Layer 4) - Correct Answer ✔✔ This layer acts as a dividing line
between the upper
layers and lower layers of the model. Data is encapsulated or decapsulated, and sent
on the appropriate path.
Provide mechanisms to transport data between network devices.
Incorporates error checking, service addressing, and segmentation.
Service addressing at the Transport Layer - Correct Answer ✔✔ Protocols such as
TCP/IP support many network
services. The transport layer ensures that data is passed to the right service at the
upper layers of the OSI model.
Segmentation at the Transport Layer - Correct Answer ✔✔ To traverse the network,
blocks of data need to be broken
into packets of a manageable size for the lower layers to handle. This process, called
segmentation, is the responsibility of the transport layer.
